The benefits of swimming in cold water

Today, Ruby shocked me by taking her first swim of 2014. It was awesome.

As you may remember from my previous post about her, Ruby is my family’s 14-year-old Lab mix (she’ll be fifteen in July!). She is a spunky, spirited dog, but due to some benign tumors in her left hip, as well as arthritis, she is in pain almost constantly.

We’ve done the best we can to keep her pain in check with medication and reassurance, but you can still very easily see how much pain she in. She limps, often keeping her back legs together and doing a “bunny-hop” to get up the front steps. She is usually in too much pain to come upstairs at night, so every night I sit and talk to her until she falls asleep at the bottom of the stairs.

But today– well, Ruby simply had an amazing day fetching sticks and walking around the fields at our favorite spot.

Fetching sticks out of the river… Ruby’s all-time favorite pasttime.

Of course, it helps that the weather is finally warmer (trust me, we New Englanders were starting to collectively lose our minds after this completely absurd winter!). But what I really think made the difference for her today is the benefits that come from swimming in cold water.

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Swimming in the cold isn’t really fun, at least for humans. Part of the reason I took so long to start working out in a pool after first hurting my knee a few years ago is that when I first tried it, I couldn’t get over how cold it was. Here I was, trying to warm my muscles up enough for them to loosen up, and I couldn’t stop shivering. My teeth were chattering audibly. What the heck.

But when I finally started doing it regularly, I was amazed to find it made an incredible difference in my pain. Here are the reasons why:

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#1: Reducing blood flow

When you immerse yourself in cold water, it causes the blood vessels in your extremities, particularly those which are the closest to the surface, to constrict. This is because your body is trying to send as little blood as possible to the periphery of your body, and keep more blood in the center of your body, to help keep your core temperature warm.

From an evolutionary perspective, this is because if we’re trapped out in the freezing cold, or we fall into a freezing lake, it’s essential that we keep our internal organs working. If it comes down to it, we can survive without a few fingers or toes. We absolutely cannot survive without a liver.

Of course, when you’re simply swimming in a chilly swimming pool, you’re not anywhere near the point of developing frostbite. But the minute your body senses that cold stimulus, it starts that process of constricting your blood vessels, which in turn limits the flow of blood to the periphery of your body.

This means that if you have a particular part of your body that’s inflamed– for example, let’s say it’s your ankle– you can temporarily stop the cycle of inflammation by reducing the flow of blood to that area. Your blood is what brings the ingredients for more inflammation to your ankle. If you reduce the flow of blood, you aren’t allowing those ingredients to come and produce more swelling. The cycle is temporarily stopped.

#2: Cold slows the rate at which your nerves send pain signals

Anyone who’s ever been outside in the winter without gloves knows this: when part of your body gets cold enough, it will start to go numb.

The pool can be a much more subtle version of this. I know that after I’ve been in the water for about ten minutes, I’ve totally forgotten about the aches and pains that were a “6” out of “10” all day.

This is because, when your nerves are cold, they simply can’t fire as fast. This gives your brain a little break from receiving all of the constant input it was receiving, which in turn can have a calming effect. By the time you’ve gotten out of the water, your brain is perceiving your pain differently, and it’s sending fewer messages to the nerves in the rest of your body asking for more “information” about the pain. Needless to say, this is good.

#3: Cold causes your body to release endorphins

Over the past few years, I have heard of many studies that show our bodies release endorphins in response to cold. (Endorphins are chemicals produced by our bodies that help relieve pain and improve mood).

I actually have a few friends who swear by taking ice cold showers to improve their mood and help them “wake up.” Of course, I’m not asking you to go swim in ice water– I think you can get the same effects with mildly chilly water.

I have personally found that chilly water makes a much bigger difference in my level of pain than the heated therapy pool I used to work out in. The therapy pool was relaxing, but I still felt all of the exact same pain that I had been feeling on land. When I switched to swimming in a regular pool (which is still heated, just not hot) I was shocked to notice that, after about ten minutes, those pains were almost completely gone.

There are many other benefits that come from working out in water. They are equally fascinating to me, so of course I will be covering them in future posts. But for now, I will leave you with this:

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A few minutes after she got out of the water today, Ruby sped up and started to prance. Completely out of the blue, she was trotting, quicker than I’d seen her move in months. I could just tell what she was thinking:

“I can move! Wow! I can move as fast as I want! I can’t believe I’m not tired!”

It was true– we hadn’t gone for a walk that long in months, let alone a walk and a swim. It was clear as day, the expression on her face.

For a moment there, we both got to see just what her body was capable of, if only we provided it with the right conditions.